[llvm] [X86][AVX] Fix handling of out-of-bounds shift amounts in AVX2 vector shift nodes (PR #84426)

[Simon Pilgrim via llvm-commits]

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@@ -521,3 +521,278 @@ define <4 x i32> @combine_vec_ashr_positive_splat(<4 x i32> %x, <4 x i32> %y) {
   %2 = ashr <4 x i32> %1, <i32 10, i32 10, i32 10, i32 10>
   ret <4 x i32> %2
 }
+
+define <8 x i16> @combine_vec16_ashr_out_of_bound(<8 x i16> %x, <8 x i16> %y) {
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RKSimon wrote:

vec16 -> v8i16

https://github.com/llvm/llvm-project/pull/84426